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Hi Justloadit,
What would you recommend for the following:
1. 2x staffrooms needing lighting, one tv, one hi-fi and two cellphone chargers? They are already cooking with gas.
2. Security Lights, solar, motion sensitive, as bright and far reaching as possible in domestic apps. Would be great if they could do 30m radius.
3. Gate motor, solar, one x 3m farm gate (with diamond mesh)
4. Shed Light, solar, bright enough to work by, double garage volume to light.
5. Newly repaired section of farmhouse with no power. At least need to light up 5 x standard rooms, cellphone/ laptop chargers x2, and some plug outlets for music system and general low power use.
Thanks

~Anything or anyone who does not bring you alive, is too small for you~ Carina
~The moment you think you know it all, is the moment you know nothing~ Carina

I am going to be a bit technical here, and hope I do not lose you in the explanation.I believe that if you understand what you are looking for, it makes it so much easier to u work out what you need.

If you go to my web page Lets Get Technical go through the articles, as there will be a better explanation on designing systems, and what is required.

I will try and make it short here.

LED lighting is the most efficient lighting for your application. So lets start there. When selecting a light source, it has to be decided if the light is for ambient use, or for reading. If you require reading, then I suggest you get a dedicated reading lamp, as opposed to attempting to light a whole room for reading, as the amount of energy required to do this will be high, which will then place a higher demand on your supply system. A high efficiency 3 watt light source, which will give approximately 350 lumens will be sufficient to light up a room for ambient light. Then what is required is to get a desk lamp with a 1 watt led for reading.

The next question required, is for how long do you need the lights to run for? Every hour of usage will require a larger storage device, and in turn will require a larger solar panel in order to replenish the energy during the day. A further question, is redundancy, if you have no sun for a day or three, how long will you require to have power for? This will again influence the size of the battery, and again the size of the solar panel to charge up the respective battery.

So effectively we can say that we require 4 watts per room for say 6 hours. This will be total consumption of 24watts. So lets say that we now need 2 day s of redundancy, totaling 72watts. Now for lead acid batteries, you only want to discharge it to 50% of its capacity to remain with in the battery specifications, which means that we will require a 144watt battery. We must now add some extra power for loses, or system inefficiencies, lets take 20%, which makes it a 172Watt battery. So for a 12V battery means that it should be around 15Amps. It just so happens that this is a standard battery size. Now we would require that the battery charges in one single day of sunlight, or effectively 6 hours of usable sun day, translating to a panel roughly 21Watts in size, however, again we must add some inefficiencies into the panel and charging electronics. We require 28Watt, the closest panel is 30W.

So for each room using 4 Watts of lighting, running of 12V D.C., the basic system, with all parts required, pole, brackets, battery, panel, enclosure, 3 watt light in fitting, wall switch, cable, excluding installation will be approximately R2650.00 excluding VAT. Reducing the redundancy will drop the price.

The outside security lights with a motion sensor, may not need a large battery, as the lights will only work when triggered, however, there is a much higher load. I reckon for your application you would want to use a 20watt security light. Expected battery life on this could be approximately 2 hours continuously on, how ever on a motion sensor, we could leave the light on for 5 minutes. This means that we could then have 24 cycles per night, and if we add 2 days redundancy for overcast days, then we would need 120Watts of power. This translates to a battery 0f 240 watts, or 20Amps. This will require a 55 watt solar panel. OK the full system, excluding installation, R5990.00 excluding VAT.

The last request is very tricky, as I would require the power consumption of the TV to be able to do any meaningful calculations. The consumption of the TV will also govern the size of the inverter.

Cellphone charging, is best done by purchasing a 12V - cigaret light charger, and charged directly of the batteries. They consume between 1 and 3 watts, depending on type. Using an inverter to get the 230V mains in order to use the mains charger is a waste of money and energy. A cigarette light charger is about R50 off the vendors at the robots, and you can even negotiate a better price. Just remember that once the phone is charged, to disconnect the charger from the battery, or else you will slowly trickle discharge the battery.

I would also suggest you invest in a minimum of a 5.5Kwatt generator, preferably gas or diesel, not petrol as a final back up in case of a complete discharge of all the batteries. Use the generator to charge the batteries.

Hope that I have provided sufficient information here. If there are any questions, pleas ask. I can tailor design the syste for you, but then I suggest a more direct approach when doing this, and a meeting would be in order.

Victor - Knowledge is a blessing or a curse, your current circumstances make you decide!Solar and LED lighting solutions - www.microsolve.co.za

I am going to be a bit technical here, and hope I do not lose you in the explanation.I believe that if you understand what you are looking for, it makes it so much easier to u work out what you need.

If you go to my web page go through the articles, as there will be a better explanation on designing systems, and what is required.

I will try and make it short here.

LED lighting is the most efficient lighting for your application. So lets start there. When selecting a light source, it has to be decided if the light is for ambient use, or for reading. If you require reading, then I suggest you get a dedicated reading lamp, as opposed to attempting to light a whole room for reading, as the amount of energy required to do this will be high, which will then place a higher demand on your supply system. A high efficiency 3 watt light source, which will give approximately 350 lumens will be sufficient to light up a room for ambient light. Then what is required is to get a desk lamp with a 1 watt led for reading.

The next question required, is for how long do you need the lights to run for? Every hour of usage will require a larger storage device, and in turn will require a larger solar panel in order to replenish the energy during the day. A further question, is redundancy, if you have no sun for a day or three, how long will you require to have power for? This will again influence the size of the battery, and again the size of the solar panel to charge up the respective battery.

So effectively we can say that we require 4 watts per room for say 6 hours. This will be total consumption of 24watts. So lets say that we now need 2 day s of redundancy, totaling 72watts. Now for lead acid batteries, you only want to discharge it to 50% of its capacity to remain with in the battery specifications, which means that we will require a 144watt battery. We must now add some extra power for loses, or system inefficiencies, lets take 20%, which makes it a 172Watt battery. So for a 12V battery means that it should be around 15Amps. It just so happens that this is a standard battery size. Now we would require that the battery charges in one single day of sunlight, or effectively 6 hours of usable sun day, translating to a panel roughly 21Watts in size, however, again we must add some inefficiencies into the panel and charging electronics. We require 28Watt, the closest panel is 30W.

So for each room using 4 Watts of lighting, running of 12V D.C., the basic system, with all parts required, pole, brackets, battery, panel, enclosure, 3 watt light in fitting, wall switch, cable, excluding installation will be approximately R2650.00 excluding VAT. Reducing the redundancy will drop the price.

The outside security lights with a motion sensor, may not need a large battery, as the lights will only work when triggered, however, there is a much higher load. I reckon for your application you would want to use a 20watt security light. Expected battery life on this could be approximately 2 hours continuously on, how ever on a motion sensor, we could leave the light on for 5 minutes. This means that we could then have 24 cycles per night, and if we add 2 days redundancy for overcast days, then we would need 120Watts of power. This translates to a battery 0f 240 watts, or 20Amps. This will require a 55 watt solar panel. OK the full system, excluding installation, R5990.00 excluding VAT.

The last request is very tricky, as I would require the power consumption of the TV to be able to do any meaningful calculations. The consumption of the TV will also govern the size of the inverter.

Cellphone charging, is best done by purchasing a 12V - cigaret light charger, and charged directly of the batteries. They consume between 1 and 3 watts, depending on type. Using an inverter to get the 230V mains in order to use the mains charger is a waste of money and energy. A cigarette light charger is about R50 off the vendors at the robots, and you can even negotiate a better price. Just remember that once the phone is charged, to disconnect the charger from the battery, or else you will slowly trickle discharge the battery.

I would also suggest you invest in a minimum of a 5.5Kwatt generator, preferably gas or diesel, not petrol as a final back up in case of a complete discharge of all the batteries. Use the generator to charge the batteries.

Hope that I have provided sufficient information here. If there are any questions, pleas ask. I can tailor design the syste for you, but then I suggest a more direct approach when doing this, and a meeting would be in order.

I'm totally agree with you.You'r 100% good here that invest in at the least a 5.5Kwatt generator, ideally gas or diesel fuel, not fuel as any back up in case of a complete release of all the battery power. Use the generator to charge the batteries.
I agreed what's said above!!!